Rare examples of hybrid chalcogenoarsenate(III) incorporating trivalent vanadium complexes.

A series of new hybrid vanadium chalcogenoarsenates(III) [V(en)AsS] (1, en = ethylenediamine), [V(dap)AsSe] (2, dap = 1,2-diaminopropane), [V(teta)AsQ] {Q = S (3) and Se (4), teta = triethylene-tetramine}, and [VIII2(en)(μ-O)][AsSe] (5) were solvothermally prepared and structurally characterized. The trigonal-pyramidal [AsQ] anions in 1-4 act as η-AsQ chelating ligands to the unsaturated trivalent vanadium complex cations [V(en/dap)]/[V(teta)], resulting in neutral molecules. 5 consists of a discrete saddle-like selenidoarsenate [AsSe] anion built up from corner-sharing [AsSe] trigonal pyramids and the dinuclear trivalent vanadium complex cation [VIII2(en)(μ-O)] constructed through two [V(en)] units bridged one μ-O group. The [V(en)] unit contains two bidentate chelating en ligands and one monodentate en ligand, and offers a rare example of an en molecule as a monodentate ligand, because the en molecule usually exhibits the bidentate chelating coordinated mode. Emphatically, although some chalcogenoarsenates combined with transition metal complexes were isolated from chelating organic amine systems by a solvothermal reaction, no trivalent vanadium complex cations are involved in combination with the chalcogenoarsenates in this synthetic method to date. Therefore, 1-5 represent rare examples of hybrid chalcogenoarsenate(III) incorporating trivalent vanadium complexes. The absorption edges of 1-5 are in the energy range of 1.43-1.62 eV, and -they exhibit distinctive photocurrent response and photoconductive properties upon visible-light illumination.